May 14, 2013 5:48 PM

Does anyone know what these creatures might be? We saw them on the beach in Formentera in the Balearics a few days ago. There were thousands of them washed up along the coastline, floating in on the waves like miniature sailing boats. Two locals told us they were Medussas (jellyfish?) but googling Medussa shows a totally different creature. I hope I have successfully attached two photos of them to help identification.

Thank you so much for your reply. We will now enjoy reading up all about these fascinating creatures. It was a very sad sight to see so many washed up on the shore and only a couple of days after seeing many thousands of jellyfish of different sizes and species being likewise washed up on the opposite side of the island.

I first saw these on the shore in northern California around 1986, and was very intrigued. A local explained they were called sailor-by-the-wind, with the 'sail' thought to be an aid to dispersal. I have never seen them since, nor thought about them. It is nice to be reminded; thanks.